Improved natural state simulation of Arjuno-Welirang Geothermal field, East Java, Indonesia

7th ITB International Geothermal Workshop

Manggala Putra, Rio Pradana^1 ; Sutopo, S.^2 ; Pratama, Heru Berian^2

Petroleum Engineering Department, Institut Teknologi Bandung, Jl. Ganesha No.10, West Java, Bandung

40132, Indonesia^1

Geothermal Engineering Department, Institut Teknologi Bandung, Jl. Ganesha No.10, West-Java-Bandung

40132, Indonesia^2

关键词: Exploration drilling;    Geothermal reservoir;    Permeability distribution;    Probabilistic methods;    Reservoir characterization;    Reservoir temperatures;    Surface manifestations;    Temperature matching;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/254/1/012022/pdf
DOI  :  10.1088/1755-1315/254/1/012022

来源: IOP

【 摘 要 】

Arjuno-Welirang Geothermal Field is a green field located across Mojokerto Regency, Malang Regency, Pasuruan Regency and Batu City in East Java Province, Indonesia. Geothermal system in Arjuno-Welirang Geothermal Field is estimated to be liquid dominated and has a reservoir temperature of about 260°C based on CO2 gas geothermometry method. Several manifestations are found at the surface; consist of hot springs, fumaroles and alterations. The field is now managed by Geo Dipa Energi. Geological, geophysical, and geochemical studies have been conducted in the field but exploration drilling has not been carried out yet until recently. For reservoir characterization and resource estimation purposes, several conceptual models have been developed based on available geoscience data. Previously, a natural state modelling attempted to match existing conceptual models has been carried out by Wardana. An entirely new natural state numerical model is made in this study to improve the result from previous model by using smaller grid blocks (40% finer). In return, the result shows more accurate temperature matching of surface manifestations than the previous model. The numerical model is developed using TOUGH2 simulator to obtain natural state condition. The objectives of this study are to develop an improved natural state numerical model; to validate temperature of the manifestations in the model with measured manifestation data; to characterize geothermal reservoir including area, thickness, pressure, temperature and permeability distribution; and to determine resource potential using probabilistic method. All data used in this paper are based on published papers.